Bulbs Flower Basics Flower Beds & Specialty Gardens Flower Garden Garden Furniture Garden Gnomes Garden Seeds Garden Sheds Garden Statues Garden Tools & Supplies Gardening Basics Green & Organic Groundcovers & Vines Growing Annuals Growing Basil Growing Beans Growing Berries Growing Blueberries Growing Cactus Growing Corn Growing Cotton Growing Edibles Growing Flowers Growing Garlic Growing Grapes Growing Grass Growing Herbs Growing Jasmine Growing Mint Growing Mushrooms Orchids Growing Peanuts Growing Perennials Growing Plants Growing Rosemary Growing Roses Growing Strawberries Growing Sunflowers Growing Thyme Growing Tomatoes Growing Tulips Growing Vegetables Herb Basics Herb Garden Indoor Growing Landscaping Basics Landscaping Patios Landscaping Plants Landscaping Shrubs Landscaping Trees Landscaping Walks & Pathways Lawn Basics Lawn Maintenance Lawn Mowers Lawn Ornaments Lawn Planting Lawn Tools Outdoor Growing Overall Landscape Planning Pests, Weeds & Problems Plant Basics Rock Garden Rose Garden Shrubs Soil Specialty Gardens Trees Vegetable Garden Yard Maintenance

What Are the Different Types of Thistles?

How to Start Lemon Seeds Indoors - watch on youtube
What Are the Different Types of Thistles?

What Are the Different Types of Thistles?. According to ZipCodeZoo.com, there are about 200 species of thistle found worldwide--in North America, Asia, Europe and northern Africa. Thistles bear spiny leaves and distinctive upright flowers.

According to ZipCodeZoo.com, there are about 200 species of thistle found worldwide--in North America, Asia, Europe and northern Africa. Thistles bear spiny leaves and distinctive upright flowers.
Types
In "The Audubon Society Field Guide to North American Wildflowers," botanist William A. Niering identifies three major thistle species found in North America: the Canada, bull and yellow thistles. The California Department of Food and Agriculture further notes the yellowspine and wavyleaf thistles as important species.
Identification
You can distinguish the bull thistle by its prickly stem. The Canada thistle, on the other hand, has a smooth stem. The yellowspine thistle spreads via vigorous lateral roots, while the wavyleaf thistle spreads weakly and produces thick, underground roots called tubers.
History
North American thistles likely belonged to a single species before the Pleistocene epoch about two million years ago. Glacier movements in the western part of the continent likely isolated groups of thistles, leading to the development of the array of species observed as of 2010, according to ZipCodeZoo.com.

Check out these related posts